Performance of new design of waveguide flange for measurements at frequencies from 800 GHz to 1.05 THz

Waveguide flange design makes major impact to measurement reproducibility in the range of sub-millimeter-wave frequencies, e.g. 1.0 THz. The fundamental performance of new flange design at millimeter wave frequency, i.e. the frequency range from 220 GHz to 330 GHz, has been investigated and presented in 2011 [1]. Its flange alignment is ensured using alignment ring with tight tolerance, then, it is fully compatible to MIL-DTL-3922/67C (UG-387) flange. This paper describes an evaluation result of its capability of connection repeatability in the WM-250 (WR-1, 750 GHz-1100 GHz) frequency band. Furthermore, the quarter wave length shim, as a TRL “through” line standard, is specially modified to fit with a new design flange, then, its capability of connection repeatability is also evaluated and discussed.